1. Field of the Invention
The invention concerns a continuous procedure for obtaining panels clad on at least two edged adjacent sides, particularly rigid or semi-rigid mineral wool panels one face of which has a cladding edged on one or two adjacent sides, used as ceilings, for example, in which case they are installed between purlings or on a suspended framework or when used as claddings--installed between vertical sections.
2. Background of the Related Art
For the soundproofing and thermal insulation of commercial, tertiary or industrial buildings, it is common practice to use relatively rigid panels, in glass wool or rock wool, clad with a vapor barrier, possibly in conjunction with a decorative cladding. A typical example is a rigid glass wool panel clad with a vapor barrier in aluminized and lacquered kraft paper, the vapor barrier being glued onto a panel reinforcement layer of glass fiber of the mesh type.
To improve the mechanical resistance of such panels and also their aesthetic appearance, it is possible to cover one or both edges with edging consisting of folding down the cladding along an angle and gluing down the part which protrudes onto the rear of the panel. Edging also facilitates handling the panels since it avoids physical contact between the hands and the mineral wool, which is frequently an unpleasant sensation. Lastly, inasmuch as the cladding itself can withstand such treatment, the edging process permits washing the panels, water no longer being able to infiltrate through the sides of the glass wool layer.
Although the advantages of the edging process are many and immediately evident, execution is not so obviously simple. Indeed, the panels which this invention deals with are fairly inexpensive products, essentially used for ceilings over large surface areas, and where the price to the customer cannot be increased considerably to cover the extra cost of providing the edging.
This basic requirement of an inexpensive process cannot be satisfied when the mineral wool panels are clad in a separate operation, as is usually the case in this type of operation, i.e., on panels ready cut to the definitive dimensions. Doing the job in separate stages has the major disadvantage of doubling the number of times the panels are handled, which requires more handling means, both in terms of tools and personnel. In addition, it is very difficult to obtain a tension of the cladding sufficient to avoid forming ugly creases, yet low enough not to cause tearing.
In addition, carrying out the cladding directly on the production line poses a number of difficulties. Firstly, the mineral wool band issuing from the polymerization oven as a general rule is as wide as the width of several panels, hence the need exists to have an extra-wide conveyor enabling spacing the panels apart in order to edge the sides in the central part of the mineral wood band. Another difficulty stems from having to pull the cladding to stretch it over the edge, yet without pulling the fibers of the mineral wool layer. One can, to a considerable degree, avoid damaging the mineral wool layer by using long fibers and a better performing binder, but this adds considerably to the cost of the process.